Colorants, dyes/pigments

Farbe,/. color dye pigment stain paint hue, tint (Leather) weak ooze, also a container for it (Lead) skimminga. 

Whereas the eadiest fluorescent-dye pigments would last only 20 days outdoors in a screen-ink film, fade resistance has been improved to such an extent that some modem daylight-fluorescent coated panels stiU have useful color after nine months or mote in Florida sunlight in a 45° exposure tack facing south. The fluorescent layer is usually coated with an acrylic film containing a uv absorber. Indoor-accelerated exposure equipment is, of course, invaluable in the development of such systems. Better dyes and resins very likely will make possible fat mote stable coatings in the future. 

W. C. Hoffman, "Dyes, Pigments, and Contact Lenses," Contact Tens Tovum Eeb. 1983. Colorants and thek use ki contact lenses. 

H. Zollinger, Color Chemisty Syntheses, Properties Applications of Organic Dyes Pigments, 2nd rev. ed., VCH PubHshers, Inc., New York, 1991. 

Farbe-malz, n. Farbmalz. -mittel, n. coloring agent, pigment, dye. farben, v.t. color, dye, stain. — in der WoUe —, dye in grain. 

Aromatic azo compounds, many of which are sulfonated, are components of many commercially important dyes, colorants, and pigments, so that attention has been directed to their degradation and transformation. These compounds are often considered recalcitrant, although then-transformation has been accomplished by reduction to amines with scission of the Ar-N=N-Ar bond to produce arylamines. The amines may then be degraded, for example, 6-aminonaphthalene-2-sulfonate by dioxygenation and ring fission to 5-aminosalicylate (Hang et al. 1991). This is then... 

Colorants. This is often the determining feature of a plastic article. Two types of colorants are used pigments and dyes. Pigments are mostly inorganic... 

The l-phenylazo-2-naphthol (7) and particularly the 2-phenylazo-l-naphthol (8) systems are used extensively, providing many of the commercial metal complex azo colorants. Azo pigments are derived from (7) whilst azo dyes are obtained from (8). Both these types of colorant exist predominantly, if not exclusively, in the hydrazone tautomeric form.8,9... 

Zollinger H (1987) Color chemistry - syntheses properties and applications of organic dyes pigments. VCH, New York... 

Because of the requirements of insolubility in water, in organic solvents and in the medium that it is being used to colour, the application processes for using pigments are quite different from those for dyes. Coloration with pigments is essentially a process of dispersion of solid particles of the pigment in a semi-solid medium. 

The pigment has recently been introduced to the market. It is a specialty product for the spin dyeing of polyamide. P.Y.192 provides somewhat dull reddish yellow shades. 1/3 SD colorations with and without TiOz are thermally stable up to 300°C. Even samples which are formulated at very low pigment concentrations completely maintain their color. The pigment offers excellent textile fastnesses, such as resistance to dry cleaning and dry heat at 200°C (Sec. 1.6.2.4). Besides,... 

Addition of low levels of certain additives to PBT can be a desirable way to enhance properties. The most common additives are colorants. Both pigments and dyes can be used to color PBT. Carbon black and titanium dioxide are most widely used. Carbon black and other pigments, for example, phthalocyanines, can also act as a nucleant for speeding crystallization. 

Uses. Chemical intermediate in the manufacture of antioxidants, antiozonants, dyes, colors, and pigments... 

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